1. Field of the Invention
The present invention relates to a plasma display panel, and more particularly, to a plasma display panel, which can improve brightness and color purity by improving a barrier structure dividing discharge cells between a front substrate and a rear substrate and make a exhausting process easy, that removes residual gas of an atmospheric pressure state contained in the PDPin a temporarily sealed condition before filled with discharge gas.
2. Background of the Related Art
FIG. 1 illustrates an exploded perspective view of a separated condition of a conventional PDP(Plasma Display Panel) and FIG. 2 illustrates a sectional view of a coupled condition of the conventional PDP. FIG. 3 illustrates a plan view of a state that stripe type barriers form cells in the conventional PDPand FIG. 4 illustrates a plan view of a state that grid type barriers form cells in the conventional PDP.
The PDPincludes a front substrate 10, which is a display screen for displaying image, and a rear substrate 20, which forms a rear surface; the front substrate and the rear substrate being coupled parallel to each other at a prescribed interval.
On a side of the front panel 10, arranged are common sustaining electrodes X and scan sustaining electrodes Y for maintaining the light emission of the cells by mutual electric discharge in one pixel, that is, sustaining electrodes, which are forms a pair respectively, including transparent electrodes (or ITO electrodes) Xa and Ya made of transparent Indium Tin Oxide material and bus electrodes Xb and Yb made of metal material.
The common sustaining electrodes X and the scan sustaining electrodes Y are covered with a dielectric layer 12 for restricting discharge current and insulating between pairs of the electrodes, and an MgO protection layer 13 is formed on an upper surface of the dielectric layer 12.
The scan sustaining electrodes Y have an addressing function for forming wall charges on the dielectric layer of the cell, to be displayed, by discharging together with address electrodes for applying data signal during an initial driving of the PDPand a discharging maintaining function for applying AC voltage after finishing the addressing.
Meanwhile, the common sustaining electrodes X perform the discharge maintaining function applying AC voltage together with the scan sustaining electrodes after finishing the addressing.
As shown in FIG. 1, the rear substrate 20 includes stripe type barriers 21 arranged parallel to one another for forming a plurality of discharge spaces, i.e., cells C, a plurality of address electrodes A arranged parallel to one another between the barriers, the address electrodes performing address discharge at portions where the address electrodes intersect the sustaining electrodes 11, and a dielectric layer 23 formed on an upper portion of the address electrodes A. Similarly, FIG. 2 illustrates a structure of the PDP, in which grid type barriers instead of the stripe type barriers are formed.
Additionally, on an upper surface of the rear substrate, namely, the surface excepting the upper end surface of the barrier 21, coated are R(Red), G(Green) and B(Blue) fluorescent layers 24 to emit visible rays for displaying image during sustaining discharge.
The operation of the PDPwill be described as follows.
Initially, if voltage of 150V˜300V is supplied between the scan sustaining electrodes Y and the address electrodes A inside an arbitrary discharge cell, writing discharge is generated in the inside of the cells located between the scan sustaining electrodes Y and the address electrodes A.
After that, if discharge voltage above 150V is supplied to the corresponding common sustaining electrode X and scan sustaining electrode Y, sustaining discharge is generated between the common sustaining electrode X and the scan sustaining electrode Y in the corresponding cell, thereby maintaining the emission of the cell for a prescribed period of time.
That is, the electric discharge between the electrodes generates electric field inside the cells, and thereby, a small amount of electrons in discharge gas are accelerated. The accelerated electrons and neutral particles in gas come into collision, thereby being ionized into electrons and ions. The ionized electrons come into collision with neutral particles, and the neutral particles are rapidly ionized into electrons and ions, so that the discharge gas is made into a plasma condition, and at the same time, vacuum ultraviolet rays are generated.
If the generated ultraviolet rays excite the fluorescent layer 24 to generate visible rays and the generated visible rays are emitted to the outside through the front substrate 10, the emission of the arbitrary cells, i.e., the image display may be recognized from the outside.
The structures of the stripe type and grid type barriers of the conventional PDPhave the following advantages and disadvantages.
The PDPadopting the stripe type barriers has a path opened vertically, thereby making a manufacturing process and a exhausting process that removes residual gas of an atmospheric pressure state contained in the PDPin a temporarily sealed condition before sealing the front and rear substrates and being filled with discharge gas, easy. However, the PDPhas a smaller area where the fluorescent layer occupies in each cell, thereby reducing light-emitting efficiency, namely, reducing brightness.
On the other hand, the PDPhaving a grid type barrier structure has a larger area where the fluorescent layer occupies in each cell, thereby increasing the light-emitting efficiency, namely, the brightness. However, the exhausting process that removes residual gas of an atmospheric pressure state contained in the PDPin a temporarily sealed condition before sealing the front and rear substrates and being filled with discharge gas can not be carried out smooth, thereby delaying a period of the exhausting process. Also, due to the complicated barriers, it is difficult to manufacture the PDP.